The way a bishop enters a school (6)
I believe the answer is:
harrow
'a school' is the definition.
(famous UK public school)
'the way a bishop enters' is the wordplay.
'the way' becomes 'how' (how something is done).
'bishop' becomes 'rr' (abbreviation for Right Reverend).
'enters' indicates putting letters inside.
'a'+'rr'='arr'
'how' placed around 'arr' is 'HARROW'.
(Other definitions for harrow that I've seen before include "Soil-breaker; school" , "Agricultural implement - cause pain to (feelings)" , "Break up (ground) - distress (feelings)" , "Farm implement with spikes" , "Soil-breaking implement" .)